This invention relates generally to tubing connection systems, and specifically to an improved apparatus and method for irrigation systems.
Many systems for irrigating crops or the like involve the assembly of lengths of tubing to each other, to form a network of pipe through which water can flow. In such applications, it is frequently useful and cost-effective to assemble such tubing on a temporary basis, pump water through it, and disassemble and remove it for use in another location or to permit plowing or other intrusive agricultural or similar operations on the soil.
Such systems commonly utilize a plurality of similarly sized and shaped tubing members, each having male and female ends that interfit with each other and permit the ready and efficient assembly of the desired irrigation system. A variety of systems and methods exist to join such members to each other for use.
One such system includes the use of channels on the male and female ends, which can be aligned with each other to form an internal annular space. By inserting an elongated plastic rod into that annular space, the two pieces of tubing can be locked together. Following use, the rod can be removed to permit the tubing to be disassembled. The rod is inserted and removed through an opening in the sidewall of the female end of the tubing, which opening passes from the outside of the assembly to the aligned internal annular space.
Although the aforementioned system permits ready assembly of tubing, the system, and particularly the rods commonly used to lock the tubing pieces to each other, have a number of shortcomings. Among other things, in large-scale agricultural applications, it is important to be able to quickly assemble and/or disassemble the irrigation tubing (so that it can be efficiently placed, moved, and used in large fields). Commonly, the tubing is stacked on truck-beds that are driven or pulled through the field as the tubing or pipe is being deployed. Optimally, the tubing is assembled together at a pace to match the truck""s speed, so that a continuous string of pipe xe2x80x9cflowsxe2x80x9d from the rear of the truckbed. The truck simply drives where the pipe is desired, and the assembled tubing is deployed behind the truck and positioned on the ground or otherwise.
Generally, the faster the tubing can be assembled, the more cost effective and time efficient the process becomes. While at any speed the system requires nimble and disciplined workers to ensure that each joint is properly aligned and that the rods are properly inserted (or properly removed during disassembly), the importance of reliable and easy assembly and insertion of the rods becomes greater as speed is increased. Among other things, the energies generated by the various components moving at higher speed increase the degree of any consequent jolts and other damage caused by misassembly, as well as increase the time required to xe2x80x9cget back up to speedxe2x80x9d.
Current rods for such purposes are of relatively basic design and construction. A representative sample is illustrated in FIG. 1, and its assembly with tubing is shown in FIG. 2. Such rods typically have a solid cylindrical body that accomplishes the desired interlocking of tubing members, but has some not insubstantial risk of jamming during insertion into the interior annular space. Among other things, the annular space is typically a rectangular cross section, and during insertion the cylindrical body can inadvertently and undesirably snag or otherwise catch or bind (from friction or otherwise).
Moreover, that risk (and the friction that is a large factor in that risk) increases the further that the rod is inserted into the annular space. Although substantially completely filling the annular space (including completely around the circumference of the joint) would maximize the strength of the tubing engagement, incrementally further inserting the rod typically requires overcoming incrementally greater resistance in the form of having to force the rod (typically a straight member) into a curved space. This forcing has to be accomplished by pushing one end of the rod, and the further xe2x80x9cinxe2x80x9d the rod goes, the more force is required and the greater the risk of xe2x80x9cjammingxe2x80x9d the rod.
If such jamming occurs, the workers must risk leaving a less-than-optimal joint between those tubing pieces, or must stop the truck and the assembly process until the rod can be repositioned or otherwise properly inserted. In either case, the quality of the process and result can be compromised.
Cylindrical rods have other drawbacks, including that longitudinal forces acting to push the tubing members away from or towards each other may experience more xe2x80x9cgivexe2x80x9d in the prior art pipe joint than is desirable. Among other things, a round cross-sectioned rod in a rectangular internal annular space in the tubing can permit or encourage the tubing members to roll or extend into and out of engagement to at least some slight degree.
In addition, in many (if not most) applications, the insertion opening can easily become covered with mud or other debris, especially as the assembly lies in a field and is used for irrigation. The mud and debris can make it difficult to locate and/or grasp the rod for removing it during disassembly of the tubing, resulting in similar risks of delay and/or damage as described above. Even without mud or debris (or even simply wetness) as a complicating factor, the typically cylindrical end of the rod can be difficult to grasp and pull in a sufficiently reliable manner to permit efficient disassembly of the irrigation pipe or tubing.
It is, therefore, an object of the invention to provide an improved apparatus and methods for assembling tubing to each other, especially for irrigation applications.
The apparatus and methods of the invention are characterized by a retaining member for temporarily connecting two pieces of tubing as described above, in which the retaining member includes an elongated body having one or more serrations or notches along its length. The notches allow the body to bend or flex more readily within the annular cavity formed by the aligned interior and exterior channels of the tubing members.
Another object of the invention is the provision of a retaining member of the aforementioned character, in which the retaining member has a cross-section that approximates the cross-section of the annular cavity formed between the tubing members. For example, in applications in which that cavity has a generally rectangular cross-section, the retaining member likewise has a generally rectangular cross-section of approximately the same dimensions. This helps provide a snug and reliable joint between the tubing members. Among the various modifications of this feature are embodiments in which the surfaces of the retaining member that approximates the cross-section of the annular cavity include at least the surfaces of the retaining member that confront and contact the annular cavity when longitudinal axial forces are applied to the tubing members.
A further object of the invention is the provision of a retaining member of the aforementioned character, in which the retaining member""s elongated body includes a first end and a second end, with the first end tapered to facilitate insertion of the end into the cavity formed between the tubing members. The second end can include a gripping portion, which portion can include one or more concave finger grips formed therein.
Yet another object of the invention is the provision of an improved water distribution system that can be readily assembled and/or disassembled. The system includes a plurality of generally rigid tubing members each having a male end and a female end, each of the male ends having an exterior channel formed therein and each of the female ends having an interior channel formed therein, with the female ends configured to matingly receive the male end of an adjacent of the tubing members so that the interior and exterior channels of the respective tubing members are substantially aligned to define an annular bore disposed partially in the male end and partially in the female end. Each of the female ends further includes a passage from the interior channel through the tubing sidewall of the female end. The system includes a plurality of similar elongated strips or splines, each insertable through any of the passages and into the corresponding annular bore, with each of the strips including a plurality of body portions hinged to adjacent such body portions to permit flexing of the strip as it is inserted through the passage and into the annular bore.
An additional object of the invention is to provide a system of the aforementioned character, in which the elongated strips of the system generally approximate the cross-sectional shape and dimensions of the annular bore. The elongated strips include a gripping portion configured to remain outside the passage, and can include one or more concave finger grips formed therein.
Another object of the invention is to provide a method of irrigation, including the steps of providing a first piece of tubing, the first piece having a female end with an annular groove formed in the interior of the female end and spaced therefrom and having a passage from the interior annular groove to an exterior surface of the first piece; providing a second piece of tubing, the second piece having a male end with an annular groove formed in the exterior of the male end and spaced therefrom; inserting the male end into the female end so that the interior and exterior grooves are substantially aligned with each other; providing a spline configured to substantially fill the aligned interior and exterior grooves; and inserting the spline through the passage and into the aligned interior and exterior grooves.
A still further object of the invention is the provision of a method of the aforementioned character, in which the spline includes an elongated body portion, the body portion having a plurality of serrations along its length to provide flexibility to the body portion. The spline can include a grippable head portion and the method can include the further steps of flowing liquid through the assembled first and second pieces of tubing and thereafter removing the spline from the aligned grooves and removing the male end from the female end.
Yet another object of the invention is the provision of a method of the aforementioned character, in which the first piece of tubing includes an opposing male end identical to the male end of the second piece of tubing, and the second piece of tubing includes an opposing female end identical to the female end of the first piece of tubing, and the method includes the steps of providing a plurality of the first and second pieces; providing a plurality of the splines; and assembling the tubing pieces together in an end-to-end manner with adjacent of the tubing pieces by inserting the male ends into adjacent of the female ends and inserting one of the splines at each such interface of male and female ends.
Other objects and advantages of the invention will be apparent from the following specification and the accompanying drawings, which are for the purpose of illustration only.